The present application generally relates to electric power steering (EPS) systems, and particularly to EPS with advanced driver assist systems (ADAS).
The Society of Automotive Engineers (SAE) in SAE Standard J3016 has defined six levels of driving automation: 0 (no automation), 1 (driver assistance), 2 (partial automation), 3 (conditional automation), 4 (high automation), and 5 (full automation). For example, FIG. 1 depicts some of the example levels determined in the SAE J3016 standards. SAE Level 3 autonomy requires that execution of and monitoring of (the) driving environment be handled by a system while the fallback performance of dynamic driving tasks be the responsibility of a human driver. As ADAS transform the auto-industry, EPS systems are adapting to accommodate that market segment. For example, EPS systems are desired that support use cases that are SAE Level 3 compatible in the short-term, which eventually operate in Level 4, the levels being those determined by the SAE J3016 standards related to on-road motor vehicle automated driving systems.
Accordingly, it is desirable to develop EPS systems that are compatible with the proposed standards. For example, it is desirable that the EPS system determine a mode of operation between a highly automated operating mode and a fully automated operating mode. Further, it is desirable that the EPS system hardware be controllable to handle inertial effects of steering wheel that is no longer in use in the fully automated operating mode. Further yet, it is desirable that EPS systems monitor and record diagnostics appropriately, for example torque sensor faults, which are unique per mode of operation.